/**
 * æä»¶å¤çç±»
 */
var fileUtils = {
		
		/*è·åæä»¶ç±»å*/
		getFormatClass: function (format){
				//åæï¼https://blog.csdn.net/qq_33769914/article/details/80021613 
				/* var arrs = [
					["doc", "doc","docx","dotx","dot","docm","dotm","xps","mht","mhtml","rtf","xml","odt"],//ææ¡£
					["pdf", "pdf"],//pdf
					["audio", "mp3"],//mp3
					["xls", "xls","xlsx","xlsb","xlsm","xlst"],//è¡¨æ ¼
					["img", "jpg","jpeg","png","gif","bmp","jpeg2000"],//å¾ç
					["zip", "rar","zip"],//åç¼©å
					["video", "mp4","avi","rm","rmvb","wmv","f4v","flv"]//å½±é³
				]; */
				var arrs = [
					["doc", "doc","docx"],//ææ¡£
					["ppt", "ppt","pptx"],//ppt]
					["pdf", "pdf"],//pdf
					["audio", "mp3"],//mp3
					["xls", "xls","xlsx"],//è¡¨æ ¼
					["img", "jpg","jpeg","png","gif","bmp","jpeg2000"],//å¾ç
					["zip", "rar","zip"],//åç¼©å
					["video", "mp4","avi","rm","rmvb","wmv","f4v","flv"]//å½±é³
				];
				
				var map = {};
				for(var i = 0; i < arrs.length; i++){
					var arr = arrs[i];
					for(var j = 1; j < arr.length; j++){
						var str = arr[j];
						map[str] = arr[0];
					}
				}
				
				if(format){
					var type = map[format];
					if(type){
						return type;
					}
				}
				return "unknown";
			}
		
}